/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

/* 主容器 */
center {
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
}

/* 标题样式 */
h1 {
    color: white;
    font-size: 2.5em;
    margin: 20px 0;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
    background: linear-gradient(45deg, #ff6b6b, #feca57, #48dbfb, #ff9ff3);
    background-size: 400% 400%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: gradient 3s ease infinite;
}

@keyframes gradient {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* 导航链接样式 */
.nav-links {
    display: flex;
    gap: 30px;
    margin: 20px 0;
    flex-wrap: wrap;
    justify-content: center;
}

.nav-links a {
    display: inline-block;
    padding: 12px 24px;
    background: linear-gradient(45deg, #ff6b6b, #ee5a24);
    color: white;
    text-decoration: none;
    border-radius: 25px;
    font-weight: bold;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.nav-links a:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.3);
    background: linear-gradient(45deg, #ff9ff3, #f368e0);
}

.nav-links a:nth-child(2) {
    background: linear-gradient(45deg, #48dbfb, #0abde3);
}

.nav-links a:nth-child(2):hover {
    background: linear-gradient(45deg, #00d2d3, #54a0ff);
}

/* 搜索表单样式 */
.search-form {
    margin: 20px 0;
    display: flex;
    gap: 10px;
    align-items: center;
    background: rgba(255,255,255,0.1);
    padding: 20px;
    border-radius: 15px;
    backdrop-filter: blur(10px);
}

.search-form input[type="text"] {
    padding: 12px 20px;
    border: none;
    border-radius: 25px;
    font-size: 16px;
    width: 300px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.search-form input[type="text"]:focus {
    outline: none;
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    transform: scale(1.05);
}

.search-form input[type="submit"] {
    padding: 12px 30px;
    background: linear-gradient(45deg, #00b894, #00cec9);
    color: white;
    border: none;
    border-radius: 25px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.search-form input[type="submit"]:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0,0,0,0.3);
    background: linear-gradient(45deg, #00cec9, #81ecec);
}

/* 表格样式增强 */
.tb-book {
    width: 90%;
    border-collapse: collapse;
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    margin: 20px 0;
    line-height: 2.5em;
}

.tb-book th {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #ffffff;
    line-height: 3em;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 14px;
    position: relative;
}

.tb-book th:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80%;
    height: 2px;
    background: rgba(255,255,255,0.5);
}

.tb-book td, .tb-book th {
    padding: 15px;
    text-align: center;
    border-bottom: 1px solid #f1f1f1;
}

.tb-book tr:nth-child(even) {
    background-color: #f8f9fa;
}

.tb-book tr:hover {
    background-color: #e3f2fd;
    transform: scale(1.01);
    transition: all 0.2s ease;
}

.tb-book tr:last-child td {
    border-bottom: none;
}

/* 链接按钮样式 */
.tb-book a {
    display: inline-block;
    padding: 8px 16px;
    background: linear-gradient(45deg, #ff6b6b, #ee5a24);
    color: white;
    text-decoration: none;
    border-radius: 15px;
    font-size: 12px;
    font-weight: bold;
    transition: all 0.3s ease;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.tb-book a:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.tb-book a:nth-child(2) {
    background: linear-gradient(45deg, #48dbfb, #0abde3);
}

.tb-book a:nth-child(2):hover {
    background: linear-gradient(45deg, #00d2d3, #54a0ff);
}

/* 表单页面样式 */
.form-container {
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.1);
    margin: 20px 0;
    width: 90%;
    max-width: 600px;
}

.form-container h2 {
    color: #333;
    margin-bottom: 30px;
    text-align: center;
    font-size: 2em;
}

.form-container form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.form-container input[type="text"],
.form-container input[type="number"],
.form-container textarea {
    padding: 15px;
    border: 2px solid #e1e1e1;
    border-radius: 10px;
    font-size: 16px;
    transition: all 0.3s ease;
}

.form-container input[type="text"]:focus,
.form-container input[type="number"]:focus,
.form-container textarea:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-container textarea {
    resize: vertical;
    min-height: 100px;
    font-family: inherit;
}

.form-container input[type="submit"] {
    padding: 15px;
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 10px;
}

.form-container input[type="submit"]:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .tb-book {
        width: 100%;
        font-size: 14px;
    }

    .nav-links {
        flex-direction: column;
        gap: 15px;
    }

    .search-form {
        flex-direction: column;
        width: 100%;
    }

    .search-form input[type="text"] {
        width: 100%;
    }

    h1 {
        font-size: 2em;
        text-align: center;
    }
}

/* 加载动画 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.tb-book {
    animation: fadeIn 0.6s ease-out;
}

/* 成功消息样式 */
.success-message {
    background: linear-gradient(45deg, #00b894, #00cec9);
    color: white;
    padding: 15px 25px;
    border-radius: 10px;
    margin: 20px 0;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}